Drum unit

Abstract

To provide a technique to facilitate circulation of gas in a body frame in which a drum unit is mounted.SOLUTION: A drum unit 2 has a first wall 74. The first wall 74 has a vent hole 80. The vent hole 80 is a hole that penetrates the first wall 74 in a second direction. With the drum unit 2 mounted in a body frame of an image forming apparatus, gas circulates through the vent hole 80 in the first wall 74. This facilitates circulation of gas in the body frame in which the drum unit 2 is mounted.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present disclosure relates to a drum unit. [Background technology]

[0002] 2. Description of the Related Art Conventionally, electrophotographic image forming apparatuses such as laser printers, LED printers, etc. are known. A conventional image forming apparatus is described in, for example, Patent Document 1.

[0003] The image forming apparatus of Patent Document 1 includes a developing cartridge having a developing roller and a drum unit having a photosensitive drum. The developing cartridge is attached to the drum unit. The drum unit with the developing cartridge attached is attached to a main body frame of the image forming apparatus. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2019-179129 A Summary of the Invention [Problem to be solved by the invention]

[0005] This type of image forming device is equipped with a circuit board having a processor such as a CPU. The image forming device also has a fuser that fuses toner to print paper. The circuit board and fuser become hot during operation of the image forming device. For this reason, the image forming device is equipped with a fan. When the fan is rotated, an airflow is generated within the main body frame of the image forming device. This allows the circuit board and fuser to be cooled.

[0006] However, the drum unit attached to the main body frame may obstruct the airflow.

[0007] An object of the present disclosure is to provide a technique for easily circulating gas within a main body frame in which a drum unit is mounted. [Means for solving the problem]

[0008] The first disclosure is a drum unit that can be attached to a main body frame of an image forming device, comprising a photosensitive drum that can rotate about a drum axis extending in a first direction, and a drum frame that rotatably supports the photosensitive drum, the main body frame having an insertion opening at one end in a second direction that intersects the first direction, the drum unit being attached to the main body frame via the insertion opening, the drum frame having a wall located at an end closest to the insertion opening, of both ends of the drum frame in the second direction when attached to the main body frame, the wall extending in the first direction and a third direction that intersects the first direction and the second direction, and the wall having an air hole penetrating in the second direction.

[0009] A second disclosure is the drum unit of the first disclosure, wherein the length of the air hole in the first direction is longer than the length in the third direction.

[0010] A third disclosure is the drum unit of the second disclosure, wherein a width of the air hole in the third direction is 8 mm or less.

[0011] A fourth disclosure is the drum unit according to any one of the first to third disclosures, wherein the wall has a plurality of the air holes.

[0012] A fifth disclosure is the drum unit according to the fourth disclosure, wherein the plurality of air holes are aligned in the first direction and the third direction.

[0013] A sixth disclosure is the drum unit of the fifth disclosure, characterized in that the wall has a plurality of first ribs extending in the first direction between the air holes adjacent to each other in the third direction, and a plurality of second ribs extending in the third direction between the air holes adjacent to each other in the first direction.

[0014] A seventh disclosure is the drum unit of the sixth disclosure, characterized in that an end of the second rib in the third direction is longer in the second direction than the first rib.

[0015] An eighth disclosure is a drum unit according to any one of the first to third disclosures, characterized in that the wall has a drum handle aligned with the air vent in the third direction, and has a recess on the opposite side of the air vent in the third direction.

[0016] A ninth disclosure is a drum unit according to any one of the first to third disclosures, characterized in that the drum frame is capable of mounting a developing cartridge, and when the developing cartridge is mounted to the drum frame, the wall protrudes in the third direction further than the developing cartridge.

[0017] The tenth disclosure is the drum unit of the ninth disclosure, wherein the developing cartridge has a developing handle having a recess, and when the developing cartridge is attached to the drum frame, the developing handle faces the air hole in the second direction.

[0018] An eleventh disclosure is a drum unit according to any one of the first to third disclosures, characterized in that the main body frame has a cover that covers the insertion opening and has a cover hole that penetrates in the second direction, and when the cover covers the insertion opening, the cover hole and the air hole face each other in the second direction. Effect of the Invention

[0019] According to the first to eleventh disclosures, gas flows through the ventilation holes in the wall of the main body frame to which the drum unit is attached, which makes it easier for gas to flow through the main body frame.

[0020] Moreover, according to the third disclosure, it is possible to prevent a user's fingers from entering the ventilation hole.

[0021] Moreover, according to the sixth disclosure, the second rib can suppress the first rib from being deflected.

[0022] Moreover, according to the seventh disclosure, the rigidity of the second rib can be improved.

[0023] Furthermore, according to the eighth disclosure, it is possible to prevent the user's hand from blocking the air hole when gripping the drum handle.

[0024] According to the ninth disclosure, when the drum unit is attached to the main body frame, the user can be prevented from touching the developer cartridge. This can prevent the developer cartridge from being misaligned with respect to the drum frame. Also, when the drum unit is attached to the main body frame, the photosensitive drum can be prevented from being irradiated with light from outside the main body frame. [Brief description of the drawings]

[0025] [Figure 1] FIG. 1 is a schematic diagram of an image forming apparatus. [Diagram 2] FIG. [Diagram 3] FIG. [Figure 4] 2 is a cross-sectional view of the developing cartridge taken along a plane perpendicular to a first direction. FIG. [Diagram 5] FIG. [Figure 6] FIG. [Figure 7] FIG. 2 is a perspective view of the drum unit in which four developing cartridges are mounted. [Figure 8] FIG. 2 is a plan view of a number of vents. [Figure 9] 3 is a partial vertical cross-sectional view of the image forming apparatus in a state in which a drum unit with a developing cartridge mounted therein is mounted on a main body frame. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0027] In the following, the direction in which the drum axis of the photosensitive drum extends is referred to as the "first direction." Furthermore, the direction in which one end of the main frame where the insertion port is located is aligned with the other end of the main frame is referred to as the "second direction." The first direction and the second direction intersect with each other. Furthermore, the direction that intersects with the first direction and the second direction is referred to as the "third direction."

[0028] Preferably, the first direction and the second direction are perpendicular to each other. Preferably, the second direction and the third direction are perpendicular to each other. Preferably, the third direction and the first direction are perpendicular to each other.

[0029] <1. Configuration of image forming device> FIG. 1 is a schematic diagram of an image forming apparatus 100. This image forming apparatus 100 is an electrophotographic printer. Specifically, the image forming apparatus 100 is a laser printer or an LED printer. As shown in FIG. 1, the image forming apparatus 100 includes a main body frame 101, a drum unit 2, and four developing cartridges 1. The four developing cartridges 1 can be attached to the drum unit 2. Furthermore, the drum unit 2 with the four developing cartridges 1 attached thereto can be attached to the main body frame 101. The image forming apparatus 100 prints an image on the surface of a printing paper using toner supplied from the developing cartridges 1.

[0030] 1, main body frame 101 has an insertion opening 102 and a cover 103. Insertion opening 102 is an opening located at one end of main body frame 101 in the second direction. Cover 103 is movable between an open position where insertion opening 102 is opened and a closed position where insertion opening 102 is closed.

[0031] When the drum unit 2 is attached to the main body frame 101, the cover 103 is placed in the open position. Then, the drum unit 2 is inserted into the main body frame 101 through the insertion opening 102. After the drum unit 2 is attached to the main body frame 101, the cover 103 is placed in the closed position. This closes the insertion opening 102.

[0032] <2. Structure of the developing cartridge> 2 and 3 are perspective views of the developing cartridge 1. Fig. 4 is a cross-sectional view of the developing cartridge 1 taken along a plane perpendicular to the first direction. As shown in Figs. 2 to 4, the developing cartridge 1 includes a housing 10 and a developing roller 20.

[0033] <2-1. Cabinet> The housing 10 is a container capable of storing toner. The housing 10 has a first outer surface 11 and a second outer surface 12. The first outer surface 11 is located at one end of the housing 10 in the first direction. The second outer surface 12 is located at the other end of the housing 10 in the first direction. The first outer surface 11 and the second outer surface 12 are separated from each other in the first direction.

[0034] A storage chamber 13 is provided inside the housing 10. Toner is stored in the storage chamber 13. As shown in Fig. 4, the housing 10 has a supply port 14. The supply port 14 is located at one end of the housing 10 in the third direction. The external space of the housing 10 and the storage chamber 13 communicate with each other via the supply port 14.

[0035] <2-2. Developing roller> The developing roller 20 is a roller that can rotate about a development axis that extends in the first direction. The developing roller 20 is located at the supply port 14 of the housing 10. That is, the developing roller 20 is located at one end of the housing 10 in the third direction.

[0036] The developing roller 20 has a developing roller body 21 and a developing roller shaft 22. The developing roller body 21 is a cylindrical member extending in a first direction. The developing roller body 21 is made of, for example, elastic rubber. The developing roller shaft 22 is a columnar member extending in the first direction through the developing roller body 21. The developing roller body 21 is fixed to the developing roller shaft 22.

[0037] The toner in the housing 10 is supported on the outer peripheral surface of the developing roller body 21. As shown in Fig. 4, the developing cartridge 1 has a blade 25. The blade 25 is located at the supply port 14. The blade 25 shapes the toner supported on the outer peripheral surface of the developing roller body 21 to a predetermined thickness.

[0038] <3. Drum unit configuration> 5 and 6 are perspective views of the drum unit 2. The drum unit 2 includes four photoconductor drums 60 and a drum frame 70.

[0039] <3-1. Photoconductor drum> The photosensitive drum 60 is a drum that is rotatable about a drum axis D that extends in the first direction. The photosensitive drum 60 is located at one end of the drum frame 70 in the third direction. The photosensitive drum 60 has a cylindrical outer circumferential surface centered on the drum axis D. The outer circumferential surface of the photosensitive drum 60 is covered with a photosensitive material. The four photosensitive drums 60 are arranged in the second direction.

[0040] <3-2. Drum frame> The drum frame 70 supports the four photosensitive drums 60 rotatably about a drum axis D. The drum frame 70 has a first side frame 71, a second side frame 72, four connecting frames 73, a first wall 74, and a second wall 75.

[0041] The first side frame 71 is located at one end of the drum frame 70 in the first direction. The first side frame 71 extends in a direction intersecting the first direction. That is, the first side frame 71 extends in the second direction and the third direction. The first side frame 71 is formed of, for example, resin. However, the first side frame 71 may be formed of multiple plates. Also, some of the multiple plates that form the first side frame 71 may be formed of metal.

[0042] The second side frame 72 is located at the other end of the drum frame 70 in the first direction. The first side frame 71 and the second side frame 72 are separated in the first direction. The second side frame 72 extends in a direction intersecting the first direction. That is, the second side frame 72 extends in the second direction and the third direction. The second side frame 72 is formed of, for example, resin. However, the second side frame 72 may be formed of a plurality of plates. Also, some of the plates among the plurality of plates that form the second side frame 72 may be formed of metal.

[0043] The four connection frames 73 are located between the first side frame 71 and the second side frame 72. The four connection frames 73 connect the first side frame 71 and the second side frame 72 in the first direction. The four connection frames 73 are arranged at intervals in the second direction. Each connection frame 73 is disposed along the photoconductor drum 60.

[0044] The first wall 74 is located at one end of the drum frame 70 in the second direction. Specifically, when the drum unit 2 is attached to the main body frame 101, the first wall 74 is located at one of both ends of the drum frame 70 in the second direction that is closer to the insertion opening 102. The first wall 74 extends in a direction intersecting the second direction. That is, the first wall 74 extends in the first direction and the third direction. The first wall 74 is an example of a "wall".

[0045] The first wall 74 has a drum handle 76. The drum handle 76 is a portion that a user grips when attaching or detaching the drum unit 2 to or from the main body frame 101. The drum handle 76 is located on the outer surface of the first wall 74. The drum handle 76 has a recess 761. The recess 761 is recessed in a direction away from the photoconductor drum 60 in the third direction.

[0046] The second wall 75 is located at the other end of the drum frame 70 in the second direction. Specifically, when the drum unit 2 is attached to the main body frame 101, the second wall 75 is located at the end farther from the insertion opening 102 out of both ends of the drum frame 70 in the second direction. The second wall 75 extends in a direction intersecting the second direction. That is, the second wall 75 extends in the first direction and the third direction.

[0047] The four developer cartridges 1 are attached to the drum frame 70. Fig. 7 is a perspective view of the drum unit 2 in which the four developer cartridges 1 are attached. When the developer cartridges 1 are attached to the drum frame 70, the housing 10 is located between the first side frame 71 and the second side frame 72 in the first direction. Also, when the developer cartridges 1 are attached to the drum frame 70, the housing 10 is located between the first wall 74 and the second wall 75 in the second direction.

[0048] 5 and 6, the drum frame 70 has a pressing member 77. When the developer cartridge 1 is attached to the drum frame 70, the pressing member 77 presses the developer cartridge 1 toward the photosensitive drum 60. This presses the developer roller 20 toward the photosensitive drum 60. As a result, the developer roller 20 comes into contact with the photosensitive drum 60. More specifically, the outer circumferential surface of the developer roller 20 comes into contact with the outer circumferential surface of the photosensitive drum 60. This makes it possible to supply the toner carried on the outer circumferential surface of the developer roller 20 to the photosensitive drum 60.

[0049] <3-3.About the ventilation holes> As shown in FIG. 1, the image forming apparatus 100 includes a circuit board 105. The circuit board 105 has a processor such as a CPU. The image forming apparatus 100 also includes a fixing unit 106. The fixing unit 106 fixes toner onto a print sheet. The circuit board 105 and the fixing unit 106 become hot during operation of the image forming apparatus 100. Therefore, the image forming apparatus 100 includes a fan 107. When the fan 107 is rotated, an airflow is generated within the main body frame 101 of the image forming apparatus 100. This cools the circuit board 105 and the fixing unit 106.

[0050] As shown in Figs. 5 to 7, the first wall 74 has a plurality of ventilation holes 80. The ventilation holes 80 are holes penetrating the first wall 74 in the second direction. The ventilation holes 80 communicate between an outer space, which is a space on one side of the first wall 74 in the second direction, and an inner space, which is a space on the other side of the first wall 74 in the second direction. Therefore, the ventilation holes 80 can allow gas to flow from the outer space to the inner space or from the inner space to the outer space.

[0051] When the fan 107 is operated with the drum unit 2 attached to the main body frame 101, gas flows between the outer space and the inner space through the ventilation holes 80. This allows gas to flow easily inside the main body frame 101. As a result, the circuit board 105 and the fixing device 106 are cooled more efficiently.

[0052] 8 is a plan view of multiple ventilation holes 80. As shown in FIG. 8, each ventilation hole 80 has a slit shape extending in a first direction. That is, the length of the ventilation hole 80 in the first direction is longer than the length of the ventilation hole 80 in the third direction. It is desirable that the width of the ventilation hole 80 in the third direction is 8 mm or less. This can prevent the user's fingers from entering the ventilation hole 80.

[0053] The multiple air holes 80 are aligned in the first direction and the third direction. Specifically, multiple sets of the multiple air holes 80 aligned in the first direction are aligned in the third direction. The first wall 74 has multiple first ribs 81 and multiple second ribs 82. The first ribs 81 extend in the first direction between the air holes 80 adjacent to each other in the third direction. The second ribs 82 extend in the third direction between the air holes 80 adjacent to each other in the first direction.

[0054] The length of the first rib 81 in the first direction is longer than the length of the second rib 82 in the third direction. If the second rib 82 were not present, the first rib 81 would be more likely to bend in the third direction. By providing the second rib 82, it is possible to prevent the first rib 81 from being bent in the third direction more than in the case where the second rib 82 is not present.

[0055] The width of the first rib 81 in the second direction and the width of the second rib 82 in the second direction may be the same or different. As shown in FIG. 6, in this embodiment, of both ends of the second rib 82 in the third direction, the end farther from the photosensitive drum 60 is longer in the second direction than the first rib 81. In this way, by making at least one end of both ends of the second rib 82 in the third direction longer in the second direction than the first rib 81, the rigidity of the second rib 82 can be improved. Note that the entire second rib 82 may be longer in the second direction than the first rib 81.

[0056] The drum handle 76 is aligned with the ventilation hole 80 in the third direction. Specifically, the drum handle 76 is located between the ventilation hole 80 and the photoconductor drum 60 in the third direction. The recess 761 of the drum handle 76 is located on the opposite side of the ventilation hole 80 in the third direction. This makes it possible to prevent the user's hand from blocking the ventilation hole 80 when the user grips the drum handle 76.

[0057] Fig. 9 is a partial vertical cross-sectional view of the image forming apparatus 100 in a state where the drum unit 2 in which the developing cartridge 1 is mounted is mounted to the main body frame 101. Fig. 9 shows a cross section including the ventilation hole 80 and perpendicular to the first direction. As shown in Fig. 9, in a state where the developing cartridge 1 is mounted to the drum frame 70, the first wall 74 protrudes in the third direction further than the developing cartridge 1. That is, the end of the first wall 74 farthest from the photosensitive drum 60 is located farther from the photosensitive drum 60 than the end of the developing cartridge 1 farthest from the photosensitive drum 60.

[0058] In this way, when the drum unit 2 with the developer cartridge 1 mounted therein is attached to the main body frame 101, it is possible to prevent a user from touching the developer cartridge 1 through the insertion opening 102. This makes it possible to prevent the position of the developer cartridge 1 from shifting relative to the drum frame 70. In addition, when the drum unit 2 is attached to the main body frame 101, it is possible to prevent light from being irradiated onto the photosensitive drum 60 from outside the main body frame 101.

[0059] As shown in FIG. 9, the housing 10 of the developer cartridge 1 has a developer handle 15. The developer handle 15 is located at the other end of the housing 10 in the third direction. The developer handle 15 is a portion that a user grips when attaching or detaching the developer cartridge 1 to or from the drum unit 2. The developer handle 15 has a recess 151. When the developer cartridge 1 is attached to the drum frame 70, the recess 151 faces the ventilation hole 80 in the second direction. This ensures a space through which gas can flow inside the first wall 74 in the second direction.

[0060] 9, the cover 103 of the image forming apparatus 100 has a cover hole 104. The cover hole 104 penetrates the cover 103 in the second direction. When the drum unit 2 is attached to the main body frame 101 and the cover 103 is placed in the closed position, the cover hole 104 and the ventilation hole 80 face each other in the second direction. This allows gas to circulate in the second direction through the cover hole 104 and the ventilation hole 80.

[0061] <4. Modifications> Although one embodiment has been described above, the present disclosure is not limited to the above embodiment.

[0062] In the above embodiment, the first wall 74 has a plurality of ventilation holes 80. Specifically, the first wall 74 has 42 ventilation holes 80. However, the number of ventilation holes 80 that the first wall 74 has may be a number different from the above. In addition, the number of ventilation holes 80 that the first wall 74 has may be one.

[0063] In the above embodiment, the ventilation hole 80 has a slit shape extending in the first direction. However, the ventilation hole 80 may have a slit shape extending in the third direction. The ventilation hole 80 may have a slit shape extending obliquely with respect to the first direction and the third direction. The ventilation hole 80 may have another shape, such as a circle.

[0064] In the above embodiment, the number of developer cartridges 1 that can be attached to the drum unit 2 is four. However, the number of developer cartridges 1 that can be attached to the drum unit 2 may be one to three, or may be five or more.

[0065] Furthermore, the elements appearing in the above-described embodiment and modified examples may be combined as appropriate or some may be deleted to the extent that no contradictions arise. [Explanation of symbols]

[0066] 1: Developing cartridge 2: Drum unit 10: Housing 15: Developing handle 20: Developing roller 60: Photoconductor drum 70: Drum frame 74: 1st wall 76: Drum handle 80: Ventilation hole 81: First Rib 82: Second rib 100: Image forming device 101: Main frame 102: Insertion port 103: Cover 104: Cover hole

Claims

1. A drum unit that can be attached to a main body frame of an image forming apparatus, a photosensitive drum rotatable about a drum axis extending in a first direction; a drum frame that rotatably supports the photosensitive drum; Equipped with the main body frame has an insertion opening at one end in a second direction intersecting with the first direction, The drum unit is attached to the main body frame through the insertion opening, The drum frame is a wall located at an end of the drum frame in the second direction that is closer to the insertion opening when the drum frame is attached to the main body frame, the wall extending in the first direction and a third direction that intersects with the first direction and the second direction; having The drum unit is characterized in that the wall has an air hole penetrating in the second direction.

2. 2. The drum unit according to claim 1, The drum unit according to claim 1, wherein the length of the air hole in the first direction is longer than the length of the air hole in the third direction.

3. 3. The drum unit according to claim 2, A drum unit, wherein a width of the air hole in the third direction is 8 mm or less.

4. 4. The drum unit according to claim 1, The drum unit is characterized in that the wall has a plurality of the air holes.

5. 5. The drum unit according to claim 4, The drum unit according to claim 1, wherein the plurality of air holes are aligned in the first direction and the third direction.

6. 6. The drum unit according to claim 5, The wall is a plurality of first ribs extending in the first direction between the air holes adjacent to each other in the third direction; a plurality of second ribs extending in the third direction between the air holes adjacent to each other in the first direction; A drum unit comprising:

7. 7. The drum unit according to claim 6, a second rib extending in the third direction from the first rib to the second rib;

8. 4. The drum unit according to claim 1, The wall is a drum handle aligned with the vent hole in the third direction, the drum handle having a recess on an opposite side of the vent hole in the third direction. A drum unit comprising:

9. 4. The drum unit according to claim 1, the drum frame is capable of mounting a developing cartridge; a developing cartridge mounted on the drum frame, the developing cartridge being supported by the developing unit and the wall projecting in the third direction from the developing cartridge when the developing cartridge is mounted on the drum frame;

10. 10. The drum unit according to claim 9, The drum unit is characterized in that the developing cartridge has a developing handle having a recess, and when the developing cartridge is attached to the drum frame, the developing handle faces the air hole in the second direction.

11. 4. The drum unit according to claim 1, The main body frame includes: a cover for closing the insertion opening, the cover having a cover hole penetrating in the second direction; having The drum unit according to claim 1, wherein the cover hole and the air hole face each other in the second direction when the cover closes the insertion opening.

Images